ixgbe: added netdev_ops file to debugfs

Added the netdev_ops file to debugfs with a command to call the
ndo_tx_timeout function to give users the ability to simulate a
tx_timeout call made by the kernel.

Signed-off-by: Catherine Sullivan <catherine.sullivan@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 105 insertions, 2 deletions

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c
index 0b08b6c7497c..2dd169ee5e68 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c
@@ -34,6 +34,102 @@
 
 static struct dentry *ixgbe_dbg_root;
 
+static char ixgbe_dbg_netdev_ops_buf[256] = "";
+
+/**
+ * ixgbe_dbg_netdev_ops_open - prep the debugfs netdev_ops data item
+ * @inode: inode that was opened
+ * @filp: file info
+ *
+ * Stash the adapter pointer hiding in the inode into the file pointer
+ * where we can find it later in the read and write calls
+ **/
+static int ixgbe_dbg_netdev_ops_open(struct inode *inode, struct file *filp)
+{
+        filp->private_data = inode->i_private;
+        return 0;
+}
+
+/**
+ * ixgbe_dbg_netdev_ops_read - read for netdev_ops datum
+ * @filp: the opened file
+ * @buffer: where to write the data for the user to read
+ * @count: the size of the user's buffer
+ * @ppos: file position offset
+ **/
+static ssize_t ixgbe_dbg_netdev_ops_read(struct file *filp,
+                                         char __user *buffer,
+                                         size_t count, loff_t *ppos)
+{
+        struct ixgbe_adapter *adapter = filp->private_data;
+        char buf[256];
+        int bytes_not_copied;
+        int len;
+
+        /* don't allow partial reads */
+        if (*ppos != 0)
+                return 0;
+
+        len = snprintf(buf, sizeof(buf), "%s: %s\n",
+                       adapter->netdev->name, ixgbe_dbg_netdev_ops_buf);
+        if (count < len)
+                return -ENOSPC;
+        bytes_not_copied = copy_to_user(buffer, buf, len);
+        if (bytes_not_copied < 0)
+                return bytes_not_copied;
+
+        *ppos = len;
+        return len;
+}
+
+/**
+ * ixgbe_dbg_netdev_ops_write - write into netdev_ops datum
+ * @filp: the opened file
+ * @buffer: where to find the user's data
+ * @count: the length of the user's data
+ * @ppos: file position offset
+ **/
+static ssize_t ixgbe_dbg_netdev_ops_write(struct file *filp,
+                                          const char __user *buffer,
+                                          size_t count, loff_t *ppos)
+{
+        struct ixgbe_adapter *adapter = filp->private_data;
+        int bytes_not_copied;
+
+        /* don't allow partial writes */
+        if (*ppos != 0)
+                return 0;
+        if (count >= sizeof(ixgbe_dbg_netdev_ops_buf))
+                return -ENOSPC;
+
+        bytes_not_copied = copy_from_user(ixgbe_dbg_netdev_ops_buf,
+                                          buffer, count);
+        if (bytes_not_copied < 0)
+                return bytes_not_copied;
+        else if (bytes_not_copied < count)
+                count -= bytes_not_copied;
+        else
+                return -ENOSPC;
+        ixgbe_dbg_netdev_ops_buf[count] = '\0';
+
+        if (strncmp(ixgbe_dbg_netdev_ops_buf, "tx_timeout", 10) == 0) {
+                adapter->netdev->netdev_ops->ndo_tx_timeout(adapter->netdev);
+                e_dev_info("tx_timeout called\n");
+        } else {
+                e_dev_info("Unknown command: %s\n", ixgbe_dbg_netdev_ops_buf);
+                e_dev_info("Available commands:\n");
+                e_dev_info("    tx_timeout\n");
+        }
+        return count;
+}
+
+static const struct file_operations ixgbe_dbg_netdev_ops_fops = {
+        .owner = THIS_MODULE,
+        .open = ixgbe_dbg_netdev_ops_open,
+        .read = ixgbe_dbg_netdev_ops_read,
+        .write = ixgbe_dbg_netdev_ops_write,
+};
+
 /**
  * ixgbe_dbg_adapter_init - setup the debugfs directory for the adapter
  * @adapter: the adapter that is starting up
@@ -41,10 +137,17 @@ static struct dentry *ixgbe_dbg_root;
 void ixgbe_dbg_adapter_init(struct ixgbe_adapter *adapter)
 {
         const char *name = pci_name(adapter->pdev);
-
+        struct dentry *pfile;
         adapter->ixgbe_dbg_adapter = debugfs_create_dir(name, ixgbe_dbg_root);
-        if (!adapter->ixgbe_dbg_adapter)
+        if (adapter->ixgbe_dbg_adapter) {
+                pfile = debugfs_create_file("netdev_ops", 0600,
+                                            adapter->ixgbe_dbg_adapter, adapter,
+                                            &ixgbe_dbg_netdev_ops_fops);
+                if (!pfile)
+                        e_dev_err("debugfs netdev_ops for %s failed\n", name);
+        } else {
                 e_dev_err("debugfs entry for %s failed\n", name);
+        }
 }
 
 /**